Rotatable electrical connection



Sept. 14, 1948. D. M. PHILLIPS 2,449,138

ROTATABLE ELECTRICAL CORRECTION Filed July 5. 194:5

.Z'NVENTOR DWIGHT PHILLIPS 7 71/3 ATTORNEY Patented Sept. 14, 1948 UNITED STATES PATENT OFFICE ROTATABLE ELECTRICAL CONNECTION Dwight M. Phillips, Fullerton, Calit, assignor to Chiksan Tool Company, Brea, Calif., a corporation of California Application July 5, 1943, Serial No. 493,544

6 Claims. (01. 173-324) This invention relates to devices for connecting electrical conductors and relates more particularly to a swivel joint or swing joint for connecting multiple conductors. A general object of this invention is to provide a practical, eifective and long wearing rotary connection for telescopically related electrical conductors.

Another object of this invention is to provide a connection of the character referred to embodying positive and dependable anti-friction means connecting the sections or assemblies for relative rotation.

Another object of this invention is to provide a connection of the character referred to in which the relatively rotatable conductor receiving parts are electrically connected independently of the anti-friction mechanical connection so that the transmission of electrical energy such as high frequency current is unaffected by operation of the anti-friction connecting means.

Another object of this invention is to provide a connection of the charactermentioned that is eiiectively sealed against the entrance and escape of fluid.

Another object of this invention is to provide an electrical connection of the character referred to that is compact and light in weight, and that may be readily inspected and serviced.

The various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of the invention, throughout which description reference is madeto the accompanying drawings, in which:

Fig. 1 is a longitudinal detailed sectional view of the connection with a portion appearing in side elevation. Fig. 2 is an elevation view of one end of the connection. Fig. 3 is an enlarged fragmentary longitudinal detailed sectional view showing the means for connecting the several elements of one of the assemblies and Fig. 4 is an elevation view of the other end of the connection.

The improved electrical connection of the present invention may be said to comprise, generally, two body sections A and 13, means l connecting the sections A and B for relative rotation, means H for transmitting electrical energy through the sections A and B independently of the means 10, inner contact means I2 for inner electrical conductors and other elements the functions and details of which will be more fully described.

The body sections A and B constitute an outer tubular assembly which supports and contains the various other parts. The section A is preferably sectional to facilitate the assembling and servicing of the connection. In the construction illustrated the section A comprises two elongate parts l3 and H. The part l3 has a radial flange.

l5 at its inner end and has a tubular lip l6 extending axially beyond the flange Hi. The part H preferably has an externaldiameter substantially the same as that of the flange l5 and is engaged over the lip IE to have its inner end oppose the face of the flange. A gasket I1 is provided between the end of the part II and the face of the flange l5. Screws l8 are passed. through openings in the flange l5 and are threaded into openings in the part I4 to connect the parts It and I4. The part It is stepped or graduated in internal diameter so that it is of greater wall thickness at its inner portion. The outer end of the part l4 may have an external flange I! for coupling with other equipment.

The section B may be a simple, tubular part and is'received in the part it of the section A with clearance. In the construction illustrated the section B is of uniform internal and external diameter and is entirely received within the part ll.

The means ill for connecting the sections A and B for free relative rotation is operable to assume and transmit axial thrusts in both directions and radial thrusts in all directions, and thus positively connects the sections. The means l0 includes or provides one or more pairs of registering annular grooves 20 in the interior of the part l4 and the exterior of the section B. In the case illustrated there are two spaced pairs of grooves 20. The grooves 20 have concave walls and are formed to define races of round or cylindrical transverse cross section. Series of balls ii are provided in the registering grooves ill to connect the sections A and B for free relative rotation. The engagement of the balls it in the race grooves 20 holds the section B in spaced relation to the internal surface of the part M. It will be seen that the spaced series of balls 2| engaged in the grooves 20 are effective in maintainmg the sections A and B in the true concentric relation and positively prevent disconnection and displacement of the sections while allowing for free relative rotation between them. Radial openlugs 22 are provided in the wall of the part l3 to communicate with the pairs of grooves 20 to permil; the insertion of the balls 21 into the grooves. The openings 22 are closed by threaded plugs 23. The plugs 23 are provided at their outer ends with intersecting kerfs or grooves 24 and lock wires 25 are engaged around the part l4 and cooperate with the grooves 24' to lock the lugs in the correct positions. The lock wires 25 may be set in annular grooves in,the periphery of the part 14.

Means is provided for sealing between the sections A and B to prevent the entrance of water and other fluids into the connection. External annular grooves 26 are provided in the section B. The grooves 25 are spaced beyond the pairs of registering race grooves 29. In the case illustrated the grooves 25 are square in transverse cross section. Sealing rings 21 of synthetic rubber or the like are provided in the grooves 26. Diagonal grooves 28 are provided in the outer corners of the sealing rings 21. The grooves 28 face outwardly and toward the outer end of the section B. The sealing rings 21 tightly fit the grooves 25 and the diagonal grooves 28 give the sealing rings additional resiliency at their active corners to better seal with the surfaces of the section B and part l4. It will be seen how the sealing rings 21 spaced at opposite sides of the anti-friction connecting means l prevent the entrance of fluids and foreign matter into the connection.

The means i I serves to conduct electrical energy through the sections A and B and the outer assembiy. The section B is prepared for connection with an outer conductor or conductor assembly. As illustrated, an outer tubular conductor 39 enters a tapered socket 3i in the outer end of the part I4. A flange 32 is secured to the end of the part l4 by spaced screws 33 and has a comple-.

mentary socket 34. The conductor has an outer protective sheath and cover over the sheathing. A sheathing wedge is located within the sockets 3| and 34 and serves to secure the sheathing of the conductor 30 within the sockets. It will be seen that upon tightening of the screws 33 the conductor 30 is securely fixed to the section A. A flange part of the wedge 35 may be clamped between the flange 32 and the end of the part i4 and a gasket 36 may be engaged between the flange and the end of the part.

A swing nipple 31 of conducting material such as brass, or the like, enters the section B from its outer end and extends completely through the section B to enter the part M of the section A. A square flange 38 may be provided on the outer end of the nipple 31 to facilitate its attachment to other equipment. ,The nipple 31 passes through the section B with considerable clearance and the invention provides means for insulating the nipple from the section B.. This means includes an insulating sleeve 39 which enters the outer end of the section B and closely engages about the nipple 31. A flange 40 is provided on the outer end of the sleeve 39 and has spaced notches in its periphery. Lugs 4| project from the end of the section B and cooperate with these notches to rotatably connect the section B and. sleeve. A look nut 42 is threaded on the nipple 31 and clamps against the end of the sleeve 39. A similar insulating sleeve 43 enters the section B from its inner end and closely engages about the nipple 31. A flange 44 is provided on the sleeve 43 adjacent its end and is provided with spaced peripheral notches 45 (see Fig. 3). Lugs 46 extend from the end of the section B and cooperate with these notches to secure the section B and the sleeve 43 against relative rotation. The endof the insulating sleeve 43 has spaced notches 41 and lugs 48 project from the surface of the nipple 31 and cooperate with the notches 41 to connect the insulating sleeve 43 and the nipple 31 against relative rotation. With the construction just described the nipple 31 of conducting material is completely 4 insulated from the section B and is connected with the section B to rotate or remain stationary therewith.

Brush means are provided to electrically connect the swing nipple 31 and the section A to providefor the transmission of electrical energy through the tubular outer assembly. Two diametrically opposite radial openings 49 are provided in the thick-walled portion of the section A. Carbon brushes 50 are slidable in the inner portions of the openings 49 and. their inner ends are engageable with the periphery of the nipple 31. Plugs 5| are threaded in the outer portions of the openings 49 and springs 52 are engaged under compression between the brushes 50 and inner ends of the plugs 5|. The springs 52 constantly urge the brushes 50 inwardly against the nipple 31 to maintain electrical connection between the nipple and the section A. In the drawings the openings 49 are shown in alignment with the screws [8 but in practice it will probably be preferred to offset the openings 49 from the screws l8.

The inner contact means I! is provided to electrically connect inner electrical conductors. An assembly of insulators is provided within the tubular-outer assembly to support the inner contact means l2. A tubular insulator 53 of porcelain or the like is secured in the part l3 by porcelain cement 54 and extends axially inward in spaced relation to the internal walls of the part l3 and nipple 31. An elongate insulator 55 of porcelain, or the like, is secured in the inner portion of the sleeve or nipple 31 by cement 55. A deep socket 51 is provided in. the inner end of the insulator 55 and receives the insulator 53 with clearance. A similar socket 58 is provided in the outer end of the insulator 55.

The inner contact means 12 includes a contact plug 59 of conducting material secured in the inner portion of the tubular conductor 53 by solder 59, or the like. Wax 5| may line the interior of the insulator 53 and the adjacent interior of the part I3 to provide a flush internal surface and may cover the end of the contact plug 59. A conductor 62 provided with a sheath 63 of rubber, or

the like, extends longitudinally through the outer conductor 30 with clearance and enters the connection assembly. The conductor 52 has its end opening 65 connecting its sockets 51 and 58. The

stem 55 of the contact member 51 extends through the opening 55 and is secured therein by porcelain cement 58, or the like. The stem 55 extends into the socket 58 and its projecting portion has a socket 59 for the reception of an inner conductor. The socketed end portion of the stem 55 may have spaced saw-cuts or slots 10 so that it is resilient to better grip the conductor. The contact member 51 is disposed within the inner portion of the socket 51 of the insulator 55 and may be fixed therein by the cement 58. A socket 1| is formed in the end of the contact member 51. The socket 1| is eccentric or offset with respect to the longitudinal axis of the connection.

A polygonal or square tube 12 of copper, or the like, is secured in the socket 1| by solder, or the like. The tube 12 projects axially from the member 51 toward the contact plug 59. A carbon brush 1: is slidable in the outer portion of the tube I2 and projects from the tube. The projecting end of the brush [3 is engageable with the broad face of the contact plug 59 and the exposed end of the conductor 82. A spring 14 is provided within the tube 12 and is arranged under compression between the bottom of the socket H and the inner end of the brush I3. The spring 14 constantly urges the brush 13 against the end of the contact plug 59 and the conductor 62 to maintain electrical connection between the plug 59 and the contact member 81. It is to be observed that the contact plug 55 is rigid with relation to the section A and that'the contact member 61 is rigid with relation to the section B and the brush 13 maintains electrical connection between the relatively rotatable contact elements.

It is believed that the operation of the electrical connection will be readily understood from the foregoing detailed description.- The balls 2| engaged in the spaced race grooves 20' dependably connect the sections A and B for free relative rotation and maintain the sections in the concentric relation. The means I I provides for the uninterrupted transmission of electrical energy through the outer tubular assembly and by-passes or is independent of the anti-friction connection it.

The inner contact means I2 is dependably insulated from the outer tubular assembly and is effectively supported between two large insulators 53 and 55. The brush l3 cooperating with the plug contact 59 provides for the uninterrupted transmission of electrical energy between the two internal conductors.

Havin described only a typical preferred form and application of my invention, I do not wish to be limited or restricted by the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. An electrical connection including two tubular sections telescoping one within the other, one section being a bearing sleeve and the other a jacket around the sleeve, anti-friction members between the interior of the jacket and the exterior of the sleeve keying the sections together against relative axial movement and connecting the sections for free relative rotation, means for securing a conductor to the jacket section, an elongate tubular conducting nipple extending centrally through the bearing sleeve and adapted to be secured to another conductor, means around the nipple rigidly securing the nipple in the bearing sleeve and including electrical insulation insulating the nipple from said sleeve, and contact means within one of the sections remote from the anti-friction members maintaining electrical connection between the nipple and the jacket section.

2. An electrical connection including two tubular sections with telescoping parts, one a bearing sleeve and the other a jacket around the sleeve, anti-friction means including members between the sleeve and jacket bearing in the jacket and on the sleeve keying the sections together against relative axial movement and connecting the telescoping parts of the sections for free relative'rotation, means on one section for securing a conductor thereto, an elongate tubular conducting nipple extending through the bearing sleeve and adapted to be connected with another conductor, insulators within the bearing sleeve and surrounding the nipple and fixing the nipple in the other section and insulating the nipple therefrom, and means within one of the sections remote from the sleeve and said members for maintaining the nipple in electrical connection with the first named section.

3. An electrical connection including two tubular sections with telescoping parts one a bearing sleeve and the other a jacket around the sleeve, anti-friction members between and connecting said parts of the sections for free relative rotation, said members bearing in the jacket and on the sleeve and keying the sections together against relative axial movement, means on one section for securing a conductor thereto, an elongate tubular conducting nipple extending through the sleeve and adapted to be connected with another conductor, insulators fixing the nipple in the hearing sleeve and insulating the nipple therefrom, and means axially removed from the anti-friction members and bearing sleeve maintaining the nipple in electrical connection with the first named section, the last named means including one or more brushes on said first named section cooperating with the nipple.

4. An electrical connection including two tubular sections one having a jacket portion and the other having a bearing sleeve in the jacket portion, anti-friction members between the sleeve and jacket connecting the sections for free relative rotation and keying the sections against relative axial movement, means on one of the sections for securing a conductor thereto, a tubular conducting nipple extending through the antifriction members independently thereof and concentric with the sleeve and adapted to be connected with another conductor, insulator means extending lengthwise of the nipple securing the nipple in the other of the sections through the sleeve and insulating the nipple therefrom, means beyond one end of the insulator means maintaining the nipple in electrical connection with the first named section, and a first inner contact within and insulated from the nipple and said first named section for connection with an incoming conductor, and a second inner contact within the nipple and in contact with the first inner contact for connection with an incoming conductor.

5. An electrical connection including two tubular sections one having a jacket portion and the other having a bearing sleeve in the jacket portion, anti-friction means including members between the sleeve and jacket connecting the sections for free relative rotation and keying the sections against relative axial movement, means on one section for securing a conductor thereto, a central tubular conducting nipple adapted to be connected with another conductor, insulator means extending lengthwise of the nipple securing the nipple in the sleeve and insulating the nipple therefrom and located between the nipple v and the antifriction members, means beyond one 2 jacket and on the sleeve and connecting the sections for free relative rotation and keying the sections together against relative axial movement, means on one section for securing a. conductor thereto, a, central tubular conducting nipple in the inner section and within the sleeve and adapted to be connected with another conductor, insulator means extending lengthwise of the nipple securing the nipple in the sleeve and insulating the nipple therefrom; means beyond 10 one end of the insulator means maintaining the nipple in electrical connection with the first named section, an insulator fixed in said firstnamed section, a contact on the insulator presenting a flat axial face, an insulator fixed in the 15 nipple, a contact member on the last named insulator, means on the contact and contact memher for receiving inner conductors, and a spring urged brush contact on the member for engaging said face.

DWIGHT M. PHILLIPS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,241,127 Krapf Sept. 25, 1917 1,720,619 Baldwin July 9, 1929 2,064,585 Atienza Dec. 15, 1936 2,119,168 Kus May 31, 1938 2,193,977 Martin Mar. 19, 1940 

